Network sites and other types of interactive electronic catalog systems commonly include recommendation systems for providing recommendations of items (e.g., goods and/or services) available from the network site. The recommendations are typically generated based on monitored user activities or behaviors, such as item purchases, item viewing events, item rentals, and/or other types of item selection actions. In some systems, the recommendations are additionally or alternatively based on users' explicit ratings of items. Some systems generate recommendations of bundles of two or more items, such as items that tend to be purchased in combination. Existing processes for generating such bundle recommendations, however, often fail to adequately identify and consider the contexts in which users tend to acquire combinations of items.